The majority of consumer electrical appliances in use in the United States as well as in many other regions of the world are designed to be powered between one hot line carrying AC current and the neutral line. Many of these appliances have a plurality of functions, some combination of which is selected for each use of the appliance. However, it is not always convenient to manually select the desired functions at the appliance.
Ceiling fans which incorporate light fixtures are an excellent illustration of a multi-function electrical appliance for which manual control at the appliance proves unsatisfactory. In this instance, the electrical appliance is suspended from the ceiling and direct access to controls on the housing requires ladders or the like. Alternatively, it has been common practice to provide strings or chains depending to an accessible height from the fan housing. Nevertheless, the string often proves obtrusive to the room and is otherwise unsatisfactory.
Ceiling fans and other common electrical appliances for which the present invention would be most applicable are permanently wired into existing cable that is in place behind the walls and ceiling. It is desired to provide such appliances with remote controls which can utilize the existing cable in place between the AC power source and the appliance. Further, it is desired to provide independent remote control for two independent functions, here the light and the fan motor, by means of independent signals. The present invention is far superior to prior remote control circuits that lack this latter provision. Prior remote control circuits advanced by the Applicant which lack this independence of function are disclosed in copending applications Ser. No. 318,393, filed Nov. 5, 1981, entitled Remote Load Selector Circuit and Method; and Ser. No. 333,637, filed Dec. 23, 1981, entitled Control Circuit for Electrical Appliances.